CVE-2026-125321

Postgres MCP login throttling trusted the wrong client address

pgEdge · Postgres MCP Server HTTP login

First documented disclosure · Review checkpoint

Summary

The limiter derived client identity from an untrusted forwarding header. A caller could avoid throttling or consume another client's login allowance.

Severity and exploitation evidence

Medium · 6.5/10 · CVSS 3.1. Severity source.

Exploitation not established: The reviewed advisory does not report malicious exploitation.

Exploitation evidence source

Technical severity is not a measure of observed attacks or of risk to your deployment. Attempts, demonstrations, and successful compromise retain the qualifications in the source.

How the weakness works

The limiter derived client identity from an untrusted forwarding header.

Conditions required

The nondefault HTTP transport was reachable with authentication enabled.

Potential impact

A caller could avoid throttling or consume another client's login allowance.

Affected versions and configurations

Before 1.1.0 with authenticated HTTP transport enabled.

Fix and mitigation status

1.1.0.

Practical next steps

Upgrade the server and configure the reverse proxy to supply trustworthy client identities.

Operating lesson

Give AI retrieval and tool services database credentials scoped to the data they need.

Evidence and limits

The public disclosure was on 2026-09-03. The CVE record was published on 2026-11-10.

Sources